Spark plug



July' 14, 1931. E. F. WITTNER 814,997

SPARK PLUG Filed April 2, 1928 ATTORNEY Patented July l93l p i v 1 I UN TED STATES-PATENT OFFICE Application filed April 2, 1928. Serial No. 266,776.

This invention relates to certain novel imsleeve nut 19 which co-operates to effect conpr-ovements. in spark plugs and has for its nection between .the plug and the sleeve principal object the provision of an improved 10. The reduced end portion'of the plug 15 construction of this character which will be carries a finger 20 which is adapted to be bent 6 highly efficient in use and economical in to dispose-its end portion 21 within the center manufacture. In using spark plugs in conof the plug 15.

. nection with internal combustion engines or The sleeve 10 provides a longitudinal bore the like difliculty is frequently encountered 22in which there is frictionally fitted an elecbecause of moisture condensation on the outer trode 23 adapted to have its end portion 24:

10 surface of the plug which allows short cirdisposed a suitable distance from the end cuiting of the plug from the top thereof to portion 21 of the finger 20 for reasons well the motor frame. It is one of the many obknown in the art. The bore 22 terminates at je'cts of this invention to provide a spark plug its upper end in an enlarged bore 25 which so constructed as to prevent the admission of extends to the top of the body 10. The upper 15 moisture or other fluid into the interior of the end of the body 10 embodies a flange 26 and spark plug and which structure is such as will a clamp member 27 formed of pliable ma permit the spark plug to be expeditiously terial such as soft rubber is adapted to entaken apart for cleaning purposes. gage this flange so as to prevent displacement Other objects will appear hereinafter. of the member 27. The wire leading from 20 The invention consists in the novel combithe distributor is indicated by 28 in the draW- s5 nation and arrangement of parts to be hereinings and as understood in the art, this wire after described and claimed; is usually of the .so-called stranded type. The invention willbe best understood by The upper end of the electro 23 embodies a reference to the accompanying drawings, conical point 29 which extends'into the bore wherein a preferred form of construction is 25. The wire 28 is inserted through an openshown and in which: v I ing 30 in the clamping member 27 and ex- Fig. 1' is a side elevational view of my in-. tends down into the bore 25 and if desired, vention; and a portion of the insulation on the wire 28 Fig. 2 is a sectional detail view of the same. adjacent the end may be cut away so as to Referring more particularly to the drawdisclose the stranded-wires as shown in Fig.

ings my improved spark plug includes a 2. However, this insulation need not be re-' sleeve 10 formed of suitable material such moved for the end of the wire is arranged as porcelain or the like. This sleeve 10 has such that the conical point 29 will be forced a reduced portion 11 formed at one end thereinto the end of the wire and engage and dis- 35 of outwardly of an enlarged portion 12 tend the strands thereof and cause the wire which provides a shoulder adaptedto abut end to be wedged between the wall of the bore upon a suitable packing 13 mounted upon a 7.25 and the point 29. From the foregoing, shoulder 14 provided by the plug 15. This it is apparenti that the connection between plug 15 has its lower portion 16 reduced and the wire 28 and the terminal of the spark n threaded for threaded engagement with the plug is concealed. within the plug and opening in the head of an internal combusinasmuch as the clamping member 27 is made tion, engine or the like. Upon the top wall of pliable material it is apparent that mois- 17 of the shoulder 12 there. is likewise proture will be prevented from entering into the i 45 into the plug 15 against the ring 18 is a .will beialleviated.

vided a suitable packing 18 and threaded plug'and thus the detrimental effects thereof While I have illustrated and described the preferred form of construction for carry- 'ing my invention into effect, this is capable of variations and modifications without departing from the spirit of the invention. I, therefore, do not wish to be limited to the precise details of construction set forth but desire to avail myself of such variations and modifications as come within the scope of the appended claim.

Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

A spark plug including a sleeve, a plugstructure in which one end of said sleeve is mounted, said sleeve having a longitudinal bore extending therethrough and having an enlarged portion at the end thereof opposite the end, retained in said plug structure, an electrode extending through said bore having a conical end disposed in said enlarged portion, said enlarged portion being of a diameter substantially equal to the diameter of a wire inserted thereinto whereby when said wire is inserted into said portion the strands thereof will be forced into engage- I ment with said conical end portion to be spread outwardly to wedge said wire in said portion, a flange on said sleeve at the end thereof opposite the end retained in said plug structure a resilient cap member disposed around said wire and engaging said flange to retain said wire in position and to prevent passage of moisture intosaid enlarged portion and said bore.

In testimony whereof I aflix my signature.

EDWARD F. WITTNER. 

